T-1954; Washington Sound, Part of Orcas Island, Wash. Ter., 1889

Metadata:

Identification_Information
Data_Quality_Information
Spatial_Reference_Information
Distribution_Information
Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: Puget Sound River History Project

Originator: Department of Earth & Space Sciences, University of Washington, Box 351310

Originator: Seattle, WA 98195

Publication_Date: 10/01/03

Title: T-1954; Washington Sound, Part of Orcas Island, Wash. Ter., 1889

Geospatial_Data_Presentation_Form: map

Abstract:

Georeferenced United States Coast & Geodetic Survey Topographic Sheet T-1954; Washington Sound, Part of Orcas Island, Wash. Ter., 1889; Scale: 1:10,000; Surveyor: J.J. Gilbert

Supplemental_Information: For a comprehensive historical and technical review of the production and interpretation of early Coast & Geodetic Survey T-sheets please refer to Shalowitz, A.L. 1964. Shore and Sea Boundaries, Volumes 2. U.S. Department of Commerce, U.S. Coast and Geodetic Survey, Washington, DC. This publication is available online at http://chartmaker.ncd.noaa.gov/hsd/shallow.htm

Time_Period_of_Content: 1889

Time_Period_Information: 1889

Single_Date/Time:

Calendar_Date: 1889

Currentness_Reference: 1889

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None planned

Keywords:

Theme:

Theme_Keyword: T-sheets

Theme_Keyword: Coastal Survey

Theme_Keyword: Land Cover

Theme_Keyword: Historical

Theme_Keyword: United States Coast and Geodetic Survey

Place:

Place_Keyword: Washington State

Place_Keyword: Puget Sound

Stratum:

Stratum_Keyword: Near Shore

Stratum_Keyword: Coast

Temporal:

Temporal_Keyword: 1889

Access_Constraints:

This georeferenced image may be freely downloaded and used. Please give credit to the Puget Sound River History Project, University of Washington.

http://riverhistory.ess.washington.edu

Use_Constraints:

This georeferenced image may be freely downloaded and used. Please give credit to the Puget Sound River History Project, University of Washington.

http://riverhistory.ess.washington.edu

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Brian Collins, Amir Sheikh

Contact_Organization:

Department of Earth and Space Sciences, University of Washington

Contact_Address:

Address_Type: mailing address

Address: Department of Earth and Space Sciences

Address: Box 351310

Address: University of Washington

City: Seattle

State_or_Province: WA

Postal_Code: 98195

Country: USA

Contact_Voice_Telephone: (206) 616-6584

Contact_Facsimile_Telephone: (206) 543-0489

Contact_Electronic_Mail_Address: bcollins@u.washington.edu

Contact_Electronic_Mail_Address: asheikh@u.washington.edu

Data_Quality_Information:

Positional_Accuracy:

Horizontal_Positional_Accuracy: 5.7 meters (using 12 reliable benchmarks)

To assess an independent check of the accuracy of the registration process, benchmarks located on the T-sheets were compared to published NGS benchmarks that were retraceable to the time of the surveyed T-sheet. (Published NGS benchmark information is located at http://www.ngs.noaa.gov/cgi-bin/datasheet.prl). Only benchmarks that could be established with a high degree of certainty that existed at the time of the original T-sheet survey and were not remounted were used in the final accuracy measurement. If no current benchmarks exist or if the benchmarks have been remounted in relation to the benchmarks on the T-sheet, hard points (areas that would expect little change since the original surveys) were used to give a general indicator of the T-sheet’s registration accuracy in lieu of a more rigorous method. Thus these hard point measurements must be viewed with some caution. It should be stressed that the accuracy assessment was to check the accuracy of the overall registration process, not necessarily the accuracy of the survey itself.

NOTE: Measured distances are rounded to the nearest meter. The hand-drawn representations of benchmarks on the T-sheets are often up to 10 meters in width. To assess an independent check of the accuracy of the registration process, the measured distance is from the NGS-published coordinates to the perceived middle of the benchmark depicted on the T-sheet. In addition, the overall shape of the benchmark symbol is sometimes obscured by other symbology on the T-sheet. Thus, there is a certain level of uncertainty introduced due to the ambiguous location of the benchmark on the T-sheet.

Horizontal_Positional_Accuracy_Report:

NGS datasheets were sought for eighteen benchmarks clearly marked on this 1:10,000 scale t-sheet. Twelve pertain to NGS records and were used for the error assessment.

Station Name	PID	Date Mon/Obs	Longitude	Latitude	Distance***
BLIND 1889	TR2130	1889	122 52 40.04679	48 37 45.07450	10.583667
HOUSE RESET	TR2138	1889	122 53 35.00085	48 38 40.84570	6.560225
JUNIPER 1889	TR2127	1889	122 53 03.21553	48 40 40.27320	2.148533
KILN 1889	TR2134	1889	122 55 01.43170	48 41 00.29923	5.086736
PRECIPICE 1889	TR2128	1889	122 53 01.49148	48 38 19.13455	6.414105
RANGE 1889	TR2040	1889	122 50 53.97261	48 37 19.60210	6.818145
THISTLE RESET	TR2140	1889	122 54 34.76288	48 40 14.84598	5.519087
TONGUE RESET	TR2141	1889	122 53 59.70125	48 41 21.26418	5.129636
TOUGH 1889	TR2129	1889	122 53 02.49657	48 41 16.51474	3.244445
TRIPPLE POINT 1889	TR2119	1889	122 53 10.63273	48 35 20.46016	9.029408
TWIN ROCK RESET	TR2034	1889	122 51 53.74132	48 36 56.12221	5.103948
TWIST 1889	TR2024	1889	122 51 23.08817	48 37 58.21693	2.663281

***Measured distance (m) between T-sheet benchmark & NGS-published benchmark

Lineage:

Technician: Soleil Kelley Date: 10.13.2003

Process_Step:

Process_Description: The georeferencing of T-sheets in the Puget Sound region was funded by the Puget Sound Nearshore Project (PSNERP) http://www.pugetsoundnearshore.org/

Scanned images were obtained from University of Washington Libraries at

http://www.wsulibs.wsu.edu/holland/masc/sanjuanindex.html

The methodology used to georeference the T-sheets was modified from the previous work of Jennifer Burke (NOAA) in the Lower Columbia and Daniels et al (2001). The georeferencing and error assessment process were carried out using Erdas Imagine 8.6 and ArcGIS 8.3.

For additional information concerning the georeferencing method please refer to: http://rocky2.ess.washington.edu/riverhistory/tsheets.php

Datum Shift:

Most T-sheets do not have a current datum represented on them (i.e. NAD 27, NAD 83). Graticules (tics) marking Latitude and Longitude in the early local Puget Sound Datum (PSD) and a later update to North American Datum (NAD) projection are most often present. To calculate the X, Y shift from NAD to NAD 27, X and Y values were used from datum difference tables for survey stations around most of Puget Sound (Patton, 1999). An overall datum shift was determined for the area covered by the T-sheet by averaging the shift from a number of survey stations in or nearby that area represented on the T-sheet.

The following survey stations were used to calculate the datum shift:

Orcas, 1853

Raccoon Bluff, 1854

Lawrence, 1854

Obstruction, 1854

Registration:

For georeferencing, tics were used only surrounding areas that depicted nearshore features on the T-sheet. This was mainly done to hasten the overall process due to the magnitude of the scope of the project while maintaining the best control around areas of interest. The sheets were then rectified using a 1^st order polynomial transformation. Points that produced relatively high RMS values, as well as tic points that consistently fell outside of 4.5 meters (on a 1:10,000 scale T-sheet) of their projected UTM coordinates were omitted.

The following tic marks were used for georeferencing the initial resample:

	Longitude		Latitude
	deg	min	deg	min
1	122	55	48	42
2	122	54	48	42
3	122	53	48	42
4	122	52	48	42
5	122	56	48	41
6	122	55	48	41
7	122	54	48	41
8	122	53	48	41
9	122	52	48	41
10	122	56	48	40
11	122	55	48	40
12	122	54	48	40
13	122	53	48	40
14	122	52	48	40
15	122	51	48	40
16	122	56	48	39
17	122	55	48	39
18	122	54	48	39
19	122	53	48	39
20	122	52	48	39
21	122	51	48	39
22	122	54	48	38
23	122	53	48	38
24	122	52	48	38
25	122	51	48	38
26	122	50	48	38
27	122	54	48	37
28	122	53	48	37
29	122	52	48	37
30	122	51	48	37
31	122	49	48	37
32	122	54	48	36
33	122	53	48	36
34	122	52	48	36
35	122	51	48	36

Three resamples were performed on this data. The first resample had low error distance in general, with the exception of points 28, 31, and 35, which had errors greater than 9 meters each (RMS of first resample is 0.0831 (<0.1 for MrSid Images)). These points were removed for the second resample, and the overall RMS reduced to 0.0590. Error distances decreased in general, although the distance increased on points that were removed for resample # 2. To improve accuracy five more points with errors over 5 meters (2, 3, 15, 29, and 34) were removed for the third resample.

Several factors that can introduce error into the registration process include:

The accuracy of the graticules and projection lines drawn on the map.

Non-uniform shrinkage of the original map due to age and storage conditions.

Distortion caused by the scanning process.

Loss of resolution and distortion due to image compression.

Ability of the technician to identify appropriate survey stations that correspond to the area of the T-sheet to compute the datum shift.

Ability of the technician to identify and locate appropriate tics on the T-sheet for the transformation.

The geometric transformation method employed.

References:

Daniels, R. C. and R.H. Huxford. 2001. An error assessment of vector data derived from scanned National Ocean Service topographic sheets. Journal of Coastal Research 17: 611 – 619.

Patton, R.S., 1999. Datum Differences: Atlantic, Gulf, and Pacific Coast of the United States. U.S. Department of Commerce, U.S. Coast and Geodetic Survey, Washington D.C. (Original publication: 1936)

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Grid_Coordinate_System:

Grid_Coordinate_System_Name: Universal Transverse Mercator

Universal_Transverse_Mercator:

UTM_Zone_Number: 10

Transverse_Mercator:

Scale_Factor_at_Central_Meridian: 0.999600

Longitude_of_Central_Meridian: -123.000000

Latitude_of_Projection_Origin: 0.000000

False_Easting: 500000.000000

False_Northing: 0.000000

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: row and column

Coordinate_Representation:

Abscissa_Resolution: 2.000000

Ordinate_Resolution: 2.000000

Planar_Distance_Units: meters

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1927

Ellipsoid_Name: Clarke 1866

Semi-major_Axis: 6378206.400000

Denominator_of_Flattening_Ratio: 294.978698

Distribution_Information:

Resource_Description: Downloadable Data

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Transfer_Size: 24.630

Metadata_Reference_Information:

Metadata_Date: 20020723

Metadata_Contact: